Lactulose Breath Test Gas Production in Childhood IBS is Associated with Intestinal Transit and Bowel Movement Frequency

Abstract

Background

In adults with irritable bowel syndrome (IBS), bacterial gas production (colonic fermentation) is related to both symptom generation and intestinal transit. Whether gas production affects symptom generation, psychosocial distress, or intestinal transit in childhood IBS is unknown.

Methods

Children (ages 7-17 years) with pediatric Rome III IBS completed validated psychosocial questionnaires and a 2-week daily diary capturing pain and stooling characteristics. Stool form determined IBS subtype. Subjects then completed a 3-hour lactulose breath test for measurement of total breath hydrogen and methane production. Carmine red was used to determine whole intestinal transit time.

Results

87 children (mean age 13 ± 2.6 (SD) years) were enrolled, of whom 50 (57.5%) were female. All children produced hydrogen and 51 (58.6%) produced methane. Hydrogen and methane production did not correlate with either abdominal pain frequency/severity or psychosocial distress. Hydrogen and methane production did not differ significantly by IBS subtype. Methane production correlated positively with whole intestinal transit time (r=0.31, P<0.005) and inversely with bowel movement frequency (r= −0.245, P<0.05). Methane production (threshold 3 ppm) as a marker for identifying IBS-C had a sensitivity of 60% and specificity of 42.9%.

Conclusions

Lactulose breath test total methane production may serve as a biomarker of whole intestinal transit time and bowel movement frequency in children with IBS. However, in children with IBS, lactulose breath test hydrogen and methane production did not correlate with either abdominal pain, IBS subtype, or psychosocial distress.